Sheet material feed control apparatus

ABSTRACT

Feeding sheet material on a conveyor means continuously moving in a first direction past a gauge means is efficiently accomplished by means of a feed control means comprising elongated lifting members positioned adjacent and in some cases between the conveyor means behind the gauge means whereby when the lifting member upper surface is below the upper surface of the conveyor means the sheet material may be fed past the gauge means and when the upper surface of the lifting member is above the upper surface of the conveyor means the sheet material is out of engagement with the conveyor means and feeding is halted. Synchronized movement of the lifting members is provided by a lifting assembly which includes a pair of rotating cams, a pair of follower means riding on said cam, a rod connecting the follower means with the lifting member and a transverse beam connecting the follower means whereby movement of the cam is transmitted through the follower arms and the connecting rods to the lifting members to cause them to move together into and out of engagement with the sheet material, thereby controlling the feeding of the sheet material past the gauge means.

United States Patent [72] Inventor Pierre Lang Ecublens, Switzerland[21] Appl. No. 835,936 [22] Filed June 24, 1969 [45] Patented Oct. 12,1971 [73] Assignee J. Bobst & Sons, Inc. [32] Priority June 24, 1968 [33 Switzerland [3 1 9770/68 [54] SHEET MATERIAL FEED CONTROL APPARATUSPrimary Examiner-Joseph Wegbreit Attorney-Hill, Sherman, Meroni, Gross &Simpson ABSTRACT: Feeding sheet material on a conveyor meanscontinuously moving in a first direction past a gauge means isefficiently accomplished by means of a feed control means comprisingelongated lifting members positioned adjacent and in some cases betweenthe conveyor means behind the gauge means whereby when the liftingmember upper surface is below the upper surface of the conveyor meansthe sheet material may be fedpast the gauge means and when the uppersurface of the lifting member is above the upper surface of the conveyormeans the sheet material is out of engagement with the conveyor meansand feeding is halted. Synchronized movement of the lifting members isprovided by a lifting assembly which includes a pair of rotating earns,a pair of follower means riding on said cam, a rod connecting thefollower means with the lifting member and a transverse beam connectingthe follower means whereby movement of the cam is transmitted throughthe follower arms and the connecting rods to the lifting members tocause them to move together into and out of engagement with the sheetmaterial, thereby controlling the feeding of the sheet material past thegauge means.

PATEN'TEUBIIT 12 ml 3.612.512 SHEET 2 BF 2 gzay ejazg SHEET MATERIALFEED CONTROL APPARATUS BACKGROUND OF THE INVENTION PRIOR ART I havediscovered that feed control means of the prior art lack the efficiencyand the reliability very necessary for new high-speedsheet-material-processing apparatus. With newly developed cutters andcreasers processing more than 5,000

sheets per hour, the efliciency and reliability of the sheet-feedingapparatus therefor must be equal to the task to avoid very expensivedowntime which may result from improper feeding. It is known to employ aflat member above which is placed a stack of the sheet material and fromwhich, by a reciprocal motion, the flat member carries thelowermostpiece of sheet under a gauge in each working cycle, so as tointroduce the sheet to a processing machine. With the increasing speedof the processing machines, however, the inherent limitation of thereciprocating-type feed apparatus which include for example, thedisproportionate increase in wear and tear caused by the change in thedirection of the mass of the reciprocating table, become apparent anddictate a difi'erent and more efficient mode of sheet feeding.

SUMMARY OF THE INVENTION The problems and disadvantages associated withthe prior art are overcome by my invention in which a conveyor meanscontinuously moving in the same direction below a stack of sheetmaterial to be fed has associated therewith a sheet feed controlmechanism which operates to stop the feeding of the sheet material bylifting the stack of sheet material off of the continuously movingconveyor. The conveyor means moves in a first direction and has asubstantially coplanar upper gripping surface which pulls abottom-contacting sheet below a gauge means spaced at least apredetermined first distance above the upper surface of the conveyormeans. This first distance is at least equal to the thickness of a sheetof material. The conveyor means may comprise at least one endless beltand may be as many as or more parallel spaced endless belts.

Engagement of the bottom sheet of the stack of sheet material with theconveyor means is controlled by a feed control means comprising aplurality of elongated lifting members positioned alongside and betweensaid conveyor means. Each of the lifting members moves between a firstposition in which the upper surface of the lifting member is below theupper surface of the conveyor means and a second position in which theupper surface of the lifting member is above the upper surface of theconveyor means so that the sheet material is kept out of engagement withthe conveyor means. In an embodiment of my invention, the lifting memberis a lever pivotally connected at a first end to an adjustable pivotmeans located forward of the gauge means in relation to the direction ofthe movement of the conveyor means. Adjacent the other end or second endof the lifting member a lifting assembly is connected thereto to pivotthe lifting member about its first end. The lifting assembly includes arotating cam means with a roller on a second end of a follower armriding thereon. The first end of the follower arm may be pivoted at apoint away from the cam. A connecting rod between the lifting member andthe follower arm transmits the movement of the follower arm in responseto the cam movement of the cam up to the lifting member to cause thelifting member to move the sheet material into and out of engagementwith the conveyor means. Since the conveyor means is at least oneendless belt and since the lifting each of the belt or belts there areat least two outermost lifting members. To provide synchronized movementof the lifting members and to keep the number of elements to a minimumthere are provided in the preferred embodiment of the invention only apair of cams and follower arms, one of each being positioned adjacentthe outermost lifting members with a transverse beam extending acrossand between the follower arms so that the connecting rods may extendbetween the transverse beam and each of the lifting members. The cammeans may be a wheel configured to give two liftings of the lift membersper revolution. When the conveyor means is an endless belt riding on atleast two drive wheels there may be provided at least one wheel at aposition below the gauge means to insure that the first distance betweenthe conveyor means and the gauge is maintained constant.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantagesof the invention will be readily apparent from the following descriptionof certain preferred embodiments thereof, taken in conjunction with theaccompanying drawings, although variations and modifications may beeffected without departing from the spirit and scope of the novelconcepts of the disclosure, and in which:

FIG. 1 is an elevational schematic side view illustrating thecooperation between the elements of the combination when the liftingmember and lifting assembly are in a feed position;

FIG. 2 is a fragmentary cross-sectional schematic elevational end viewgenerally taken along the lines IIIl in FIG. 1;

FIG. 3 illustrates the feed control means in the area of the gauge meanswith the lifting member in its lowered position;

. FIG. 4 illustrates the feed control means with the lifting memberraised in the area of the gauge means; and,

FIG. 5 is a detailed cross-sectional view of the lifting membersuspension means taken along the lines V--V of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT There is shown in FIG. 1 aconveyor means 1 moving in a first direction 2 over a plurality ofrollers 3 which conveyor means is adapted to transport the lowermostsheet 50 of a stack of sheet material 5 below a gauge means 4 to aprocessing machine not shown. The movement of the remainder of the stack5 is controlled by the gauge 4. The conveyor means 1 may advantageouslybe in the form of an endless belt having a substantially coplanar uppergripping surface In and which moves over a series of rollers 3. Further,it may comprise a single endless belt or a plurality of spaced generallyparallel belts show schematically in FIG. 2. The gauge means 4 is spacedabove the upper surface of the conveyor means la a first distance 40that should be at least equal to the thickness of the sheet materialpieces 5a. The first distance or slit 4a is of an adjustable height sothat only the bottom sheet of the stack may be allowed to escape and bedrawn along by the conveyor means into the processing apparatus.

To control the feeding of the sheets from the bottom of the stack 5 lhave provided an efficient and reliable feed control means comprising aplurality of lifting members 6 which may be positioned on opposite sidesof the belt or belts which comprise the conveyor system. While they maybe adjacent each belt side edge it must be understood that otherarrangements may be suitable. The lifting member 6 is movable between afirst position as shown in FIG. 3 in which the upper surface 60 of thelifting member 6 is below the upper surface In of the conveyor means anda second position as may be seen in FIG. 4 in which the upper surface 6aof the lifting member 6 is above the upper surface In of the conveyormeans I and is in contact with the stack of sheet material 5 to therebyhold the lowermost sheet of the stack above the continuously movingconveyor means 1 so that feeding of the material is stopped. While thelifting member 6 may be of various configurations, 1

members are positioned alongside and on opposite sides of have found itadvantageous to pivot a first end of the lift member 6 about a point 7which pivot point is positioned forward of the gauge means 4 relative tothe direction of movement of the conveyor means 1. As will be explainedlater this pivot means 7 allows adjustment of the spacing between theupper surface of the lift member 6 and the lower edge of the gauge 4.With the first end of the lift member 6 pivoted at the pivot the secondend has associated therewith a lifting assembly that serves to move thelift member between the aforementioned first and second positions.

The lift assembly is connected to the lift member 6 adjacent its secondend with an attachment means 8. A connecting rod 9 is pivotally securedto said attachment means 8 by means of a pivot point 80 as may beclearly seen in FIGS. 1 and 2. The other end of the connecting rod 9 isconnected to a blockmounting means 10 which includes a clamp portion 11that pivots about a point 11a and employs a screw means 12 to clamp ontoa transverse beam 13. With each of the lifting members 6 being providedwith a lifting assembly portion identified by the numbers 8, 9, 10, 11and 12 clamped to a common transverse beam 13, which beam in turn isattached to a follower arm 14, the lift members 6 will move in responseto the pivotal movement of a follower arm 14 about a pivot 15 on thefirst end of said follower arm 14. A roller means 16 at a second end ofsaid roller arm 14 rides on a cam 17 that is operatively connected to adrive means 18 to rotate in a direction as shown for example by thearrow 17a. As the cam 17 turns, it pivots the follower arm 14 about thepivot point 15 and by means of the connecting rod 9 pivots the liftingmember 6 about the pivot 7 to raise the stack of sheet material 5 out ofcontact with the continuously moving belt I.

With the lifting members of the feed control means being positionedalongside and on opposite sides of each of the conveyor belt or belts lof the conveyor system there will always be at least two outennostlifting members with the possibility of one or more interior liftingmembers. To provide synchronization of all the lifting members and toprovide for an efficient and reliable drive means, I have found ithighly effective to provide only two cams and follower arms bypositioning these adjacent the outermost lifting members and extending atransverse beam thereacross so that the lifting members are connected tothe transverse beam rather then to the follower arm 14. In this manneralso the spacing and adjustment of the conveyor means is readilyaffected in a minimum of time by merely moving the mounting blocks alongthe transverse beam. Also of course, the movement of the lifting membets6 is synchronized. While it is possible to use a greater or lessernumber of cam and follower arm members I have not found this to benecessary. Referring to FIG. 2 it may be seen that a drawback spring 19disposed at the ends of the transverse beam 13 will urge the roller 16on the follower arm 14 into contact with the cam 17.

Referring now to FIG. 5 there may be seen an eccentric connection meansgenerally indicated at 20 which allows a variation in the elevation ofthe pivot point 7 and consequently the lifting member 6. This means isprovided so that when a sheet 5a of the stack 5 is moved forward hy theconveyor means 1 as indicated above, the pinching or clamping of thetail end of the sheet between the conveyor means 1 and the abutment 4will be avoided when the lifting member 6 moves the remainder of thestack out of engagement with the conveyor means. Thus, the firstdistance 4a must be maintained to be at least equal to the thickness ofthe sheet material. Moreover, the distance between the upper surface ofthe lifting members 6 and the bottom edge of the gauge means 4 must infact be greater then the thickness of the sheet material so that whenthe lift member 6 is moved upwardly to its second position it willremain spaced from the gauge means by a distance at least equal to saidsheet material thickness. To provide for this adjustment the pivotmember 7 for the lift members 6 is bushed in an eccentric connector 21that turns in a support member 22 affixed to the apparatus 10 foundationwhich eccentric member 21 is capable of being secured by a stop screw 23in any desired position within the range of the eccentric.

Operation of the above-described apparatus is briefly set forth withrespect to the drawings in FIG. 1 of which it may be seen that thebottom sheet 5a of the stack of sheets 5 acting under the weight of thestack, will be gripped by the upper surface la of the continuouslymoving endless belt means 1 and moved in the direction of movement 2below the gauge means 4 into a machine not shown for further processing.Control of the removal of the bottom sheet 5a is affected by moving thestack 5 into and out of engagement with the conveyor means 1. Thiscontrol is affected by lift members 6 coextensive at least with thewidth of the stack 5 and positioned initially in a first position belowthe level of the upper surface of the conveyor means 1 but pivotedupwardly by means of a lifting assembly 8-16 to a position above theupper surface la of the conveyor means 1, whereby the lowermost sheet 5aand the stack 5 are lifted out of contact with the moving belt.

Suitable drive means not shown convey their power through a shaft 18 toturn the aligned pair of cams 17. A roller 16 on each of the followerarms 14 rolls on the cam surface, raises and lowers the follower arm 14which follower arm 14 in turn operates through the connecting rod 9attached to a transverse beam 13 to move the lifting members 6 up ordown together, thereby raising and lowering the stack of sheet materialout of and into engagement with the conveyor means I. The drive meansfor the conveyor means 1 and the cam means 17 may be synchronized withthe operation of the sheet-material-processing machine not shown so thatsynchronized feeding is obtained.

By positioning the pivot means 7 in front of the gauge means 4 itassures that the entire lower surface of the bottom sheet 5a can bemoved out of contact with the conveyor means 1. It is to be understood,however, that it is possible for a small portion of the sheet 50 toremain in contact with the conveyor means since the frictional forcewill not be sufficient to move the sheet 50 from beneath the stack 5.

It is pointed out that the pivot axis 7 may be common to all of thelifting members 6 so that an eccentric pivot connection means such asshown in FIG. 5 need be provided only on opposite sides of said pivotaxis 7 to thereby keep the number of parts necessary to a minimum andfurther to assure the synchronization of operation between the liftingmembers 6. This synchronization is evident inasmuch as the liftingmembers 6 are pivoted about a common pivot point 7 and moved byidentical connecting rods 9 attached to a common transverse member 13that moves in response to aligned earns 17 attached to a common driveshaft 18.

Although minor modifications might be suggested by those versed in theart, it should be understood that I wish to embody within the scope ofthe patent warranted hereon all such modifications as reasonably andproperly come within the scope of my contribution to the art.

I claim as my invention:

1. A apparatus for selectively feeding sheet material comprising aconveyor means movable in a first direction having an upper surfacelying substantially in a plane, a gauge means spaced at least apredetermined first distance above said upper surface, a feed controlmeans controlling the elevation of sheet material with respect to saidconveyor upper surface whereby said sheet material may be moved into andout of engagement with said upper surface of said conveyor means, saidfeed control means comprising an elongated lifiing member having anupper surface which lies substantially in a plane, said lifting memberbeing movable between a first position in which said upper surface ofsaid lifting member is below said upper surface of said conveyor meansand a second position in which said upper surface of said lifting memberis above said upper surface of said conveyor means in contact with saidsheet-material to keep it out of engagement with said conveyor means,each said lifting member being a lever pivotally connected at a firstend to a pivot means located forward of said gauge means, said pivotmeans being an eccentric connection operable to vary the level of thepoint of pivot whereby said first distance may be varied.

2. An apparatus according to claim 1 wherein said conveyor meansincludes at least one strip having opposite side edges, a lifting memberbeing positioned alongside and adjacent each of said side edges.

3. An apparatus according to claim 1 wherein said lifting assemblyincludes a rotating cam means, a follower arm pivoted about a first endand having a roller on a second end, said roller riding on said cammeans, a connecting rod connected between said lifting member and saidfollower arm whereby movement of said follower arm in response to therotation of said cam is transmitted to said lifting member to cause itto move into and out of engagement with said sheet material.

4. An apparatus according to claim 3 wherein said conveyor means is atleast one endless belt and said lifting members of said feed meanscontrol are positioned alongside and on opposite sides of each of saidbelt or belts, so that there are at least two outermost lifting members,said cams and follower arms of said lifting assemblies being positionedadjacent said outermost lifting members, a transverse beam extendingacross said follower arms and a connecting rod extending between saidtransverse beam and each of said lifting members whereby the movement ofall of said lifting members is synchronized.

5. An apparatus according to claim 4 wherein said conveyor meanscomprises parallel endless belts and there are l 1 lifting memberstherebetween and alongside whereby said belts and lifting members arecoextensive in width with both said sheet material and'said gauge meansso that a stack of sheet material of great weight may be lifted quicklyand efficiently.

6. An apparatus'according to claim 3 wherein said cam means is a wheelconfigured to give two liftings per revolution.

7. An apparatus according to claim 4 wherein said endless belt runs onat least two driving rollers, one of said rollers being positioned belowsaid gauge means.

8. An apparatus for selectively feeding sheet material comprising aconveyor means movable in a first direction having an upper surfacelying substantially in a plane, a gauge means spaced at least apredetermined first distance above said upper surface, a feed controlmeans controlling the elevation of sheet material with respect to saidconveyor upper surface whereby said sheet material may be moved into andout of engagement with said upper surface of said conveyor means, saidfeed control means comprising an elongated lifting member having anupper surface which lies substantially in a plane, said lifting memberbeing movable between a first position in which said upper surface ofsaid lifting member is below said upper surface of said conveyor meansand a second position in which said upper surface of said lifting memberis above said upper surface of said conveyor means in contact with saidsheet material to keep it out of engagement with said conveyor means,each said lifting member being a lever pivotally connected at a firstend to a pivot means located forward of said gauge means, said liflingmember having a second end remote from said first end, a liftingassembly cooperating with said second end whereby said lifting assemblymay raise and lower said upper surface of said lifting member above andbelow said upper surface of said conveyor means by pivoting said liftmember about said pivot means, said first distance being at least equalto the thickness of a sheet or material and said

1. A apparatus for selectively feeding sheet material comprising aconveyor means movable in a first direction having an upper surfacelying substantially in a plane, a gauge means spaced at least apredetermined first distance above said upper surface, a feed controlmeans controlling the elevation of sheet material with respect to saidconveyor upper surface whereby said sheet material may be moved into andout of engagement with said upper surface of said conveyor means, saidfeed control means comprising an elongated lifting member having anupper surface which lies substantially in a plane, said lifting memberbeing movable between a first position in which said upper surface ofsaid lifting member is below said upper surface of said conveyor meansand a second position in which said upper surface of said lifting memberis above said upper surface of said conveyor means in contact with saidsheet material to keep it out of engagement with said conveyor means,each said lifting member being a lever pivotally connected at a firstend to a pivot means located forward of said gauge means, said pivotmeans being an eccentric connection operable to vary the level of thepoint of pivot whereby said first distance may be varied.
 2. Anapparatus according to claim 1 wherein said conveyor means includes atleast one strip having opposite side edges, a lifting member beingpositioned alongside and adjacent each of said side edges.
 3. Anapparatus according to claim 1 wherein said lifting assembly includes arotating cam means, a follower arm pivoted about a first end and havinga roller on a second end, said roller riding on said cam means, aconnecting rod connected between said lifting member and said followerarm whereby movement of said follower arm in response to the rotation ofsaid cam is transmitted to said lifting member to cause it to move intoand out of engagement with said sheet material.
 4. An apparatusaccording to claim 3 wherein said conveyor means is at least one endlessbelt and said lifting members of said feed means control are positionedalongside and on opposite sides of each of said belt or belts, so thatthere are at least two outermost lifting members, said cams and followerarms of said lifting assemblies being positioned adjacent said outermostlifting members, a transverse beam extending across said follower armsand a connecting rod extending between said transverse beam and each ofsaid lifting members whereby the movement of all of said lifting membersis synchronized.
 5. An apparatus according to claim 4 wherein saidconveyor means comprises 10 parallel endless belts and there are 11lifting members therebetween and alongside whereby said belts andlifting members are coextensive in width with both said sheet materialand said gauge means sO that a stack of sheet material of great weightmay be lifted quickly and efficiently.
 6. An apparatus according toclaim 3 wherein said cam means is a wheel configured to give twoliftings per revolution.
 7. An apparatus according to claim 4 whereinsaid endless belt runs on at least two driving rollers, one of saidrollers being positioned below said gauge means.
 8. An apparatus forselectively feeding sheet material comprising a conveyor means movablein a first direction having an upper surface lying substantially in aplane, a gauge means spaced at least a predetermined first distanceabove said upper surface, a feed control means controlling the elevationof sheet material with respect to said conveyor upper surface wherebysaid sheet material may be moved into and out of engagement with saidupper surface of said conveyor means, said feed control means comprisingan elongated lifting member having an upper surface which liessubstantially in a plane, said lifting member being movable between afirst position in which said upper surface of said lifting member isbelow said upper surface of said conveyor means and a second position inwhich said upper surface of said lifting member is above said uppersurface of said conveyor means in contact with said sheet material tokeep it out of engagement with said conveyor means, each said liftingmember being a lever pivotally connected at a first end to a pivot meanslocated forward of said gauge means, said lifting member having a secondend remote from said first end, a lifting assembly cooperating with saidsecond end whereby said lifting assembly may raise and lower said uppersurface of said lifting member above and below said upper surface ofsaid conveyor means by pivoting said lift member about said pivot means,said first distance being at least equal to the thickness of a sheet ormaterial and said pivot means comprising an eccentric connectionoperable to vary the level of the point of pivot so that when the uppersurface of said lifting member is raised above the upper level of saidconveyor means the space between said lifting member upper surface andsaid gauge means is at least equal to said first distance.